ISO/FDIS 17880

Cellular plastics — Self-supporting metal faced sandwich panels

This document specifies requirements for factory made, self-supporting, double skin metal faced insulating sandwich panels where the insulating core materials are intended to be but not limited to cellular plastics and mineral wool as defined below. The sandwich panels are intended for discontinuous laying in the following applications: a) roofs and roof cladding; b) external walls and wall cladding. The insulating core materials covered by this document are rigid polyurethane foam (PUR), polyisocyanurate foam (PIR), expanded polystyrene foam (EPS), extruded polystyrene foam (XPS), phenolic foam (PF), and mineral wool. Sandwich panels with edge details that utilize different materials from the main insulating core are included in this document. Sandwich panels used in outdoor cold store applications are included in this document. This document does not cover the following: a) sandwich panels with a declared thermal conductivity for the insulating core material greater than 0,06 W/m²K at 10 °C; b) sandwich panels consisting of two or more clearly defined layers of different insulating core materials (multi-layered); c) sandwich panels with perforated facing(s); d) curved sandwich panels; The products covered by this Document shall be controlled by the manufacturer under system 1 of ISO 12576-1. Its purpose is to provide uniform methods that are used to determine whether a production or a consignment of a thermal insulating material should be accepted as conforming to the relevant specification requirements. System 1 of ISO 12576-1 defines the manufacturer's declaration of conformity, based on the manufacturer's factory production control, based on ISO9001:2000, without any participation of a third party.

Plastiques alvéolaires — Panneaux sandwich à parements métalliques autoportants

General Information

• Status: Not Published
• ICS: 83.140.99 - Other rubber and plastics products
• Technical Committee: ISO/TC 61/SC 10 - Cellular plastics
• Drafting Committee: ISO/TC 61/SC 10/WG 10 - Plastic insulation
• Parallel Committee: ISO/TC 163 - Thermal performance and energy use in the built environment
• Current Stage: 5020 - FDIS ballot initiated: 2 months. Proof sent to secretariat
• Start Date: 11-May-2026
• Completion Date: 11-May-2026

Overview

ISO/FDIS 17880: Cellular plastics - Self-supporting metal faced sandwich panels defines the requirements for factory-made, self-supporting, double skin metal-faced insulating sandwich panels. These construction products feature a core made of insulating materials, including but not limited to cellular plastics like PUR, PIR, EPS, XPS, phenolic foam, and mineral wool. The standard focuses on panels intended for discontinuous laying in key building envelope applications such as roofs, roof cladding, external walls, and wall cladding. Additionally, the scope encompasses sandwich panels used in outdoor cold storage applications.

By establishing uniform production and conformity requirements, ISO/FDIS 17880 supports manufacturers, designers, architects, and builders in selecting and specifying sandwich panel products for thermal insulation, weather protection, and structural reliability in building projects.

Key Topics

• Panel Composition: Covers double skin metal faces (steel, stainless steel, aluminium, copper) with an insulating core such as rigid polyurethane (PUR), polyisocyanurate (PIR), expanded/extruded polystyrene (EPS/XPS), phenolic foam (PF), and mineral wool.
• Application Areas: Limits to discontinuously laid panels for roofs, walls, cladding, and outdoor cold storage. Curved and perforated panels, as well as those with multilayered or excessively high thermal conductivity cores, are excluded.
• Product Requirements:
  • Minimum physical, mechanical, and durability properties for both facings and core materials
  • Testing methods for mechanical resistance, thermal insulation, fire characteristics, and dimensional tolerances
  • Factory production control governed by ISO 12576-1, focusing on manufacturer self-declaration based on ISO 9001 principles
• Optional Panel Properties: Includes parameters such as water and air permeability, sound insulation, and absorption qualities.
• Marking & Labelling: Requirements for product identification, traceability, and packaging are defined to support correct specification and on-site handling.

Applications

Self-supporting metal faced sandwich panels standardized by ISO/FDIS 17880 are widely used in modern construction due to their excellent balance of strength, thermal insulation, and ease of installation. Common applications include:

• Roofs and Roof Cladding: Lightweight, robust panels ensure weather resistance and energy efficiency in both residential and industrial buildings.
• External Walls and Wall Cladding: Panels offer a thermally effective building envelope, suitable for new constructions and retrofits, improving both façade performance and aesthetic value.
• Outdoor Cold Storage: Compliant panels can be selected for cold store construction, ensuring optimal thermal performance under a range of outdoor conditions.
• Edge Details: The standard allows for panels with diverse edge materials, broadening design and installation possibilities while maintaining system integrity.

By adhering to ISO/FDIS 17880, manufacturers help reduce variability in sandwich panel quality, while designers and construction professionals can confidently specify materials that meet international safety, thermal, and durability benchmarks.

Related Standards

For comprehensive compliance and integration within construction projects, refer to the following related international standards:

• ISO 12576-1: Thermal insulation materials - Declaration of conformity and factory production control system
• ISO 140-3, ISO 354, ISO 717-1: Acoustics - Measurement and classification
• ISO 834 series: Fire-resistance tests for building elements
• ISO 4898, ISO 9229, ISO 6946: Thermal insulation specifications and calculation methods
• ISO 6270-1, ISO 6361, ISO 6892-1: Physical property and material testing standards
• ISO 12491: Statistical quality control methods for building materials
• ISO 11654, EN 508-1, EN 1396, EN 10088-1: Material specifications for metals and alloys used in sandwich panels

Proper application of ISO/FDIS 17880 in conjunction with these related standards ensures safety, durability, and optimal energy performance in modern building envelopes constructed with metal faced sandwich panels.

Standards Content (Sample)

DRAFT
International
Standard
ISO/DIS 17880
ISO/TC 61/SC 10
Cellular plastics — Self-supporting
Secretariat: SCC
metal faced sandwich panels
Voting begins on:
Plastiques — Panneaux sandwich à parements métalliques
2024-06-25
autoportants
Voting terminates on:
ICS: 83.140.99 2024-09-17
THIS DOCUMENT IS A DRAFT CIRCULATED
FOR COMMENTS AND APPROVAL. IT
IS THEREFORE SUBJECT TO CHANGE
AND MAY NOT BE REFERRED TO AS AN
INTERNATIONAL STANDARD UNTIL
PUBLISHED AS SUCH.
IN ADDITION TO THEIR EVALUATION AS
BEING ACCEPTABLE FOR INDUSTRIAL,
TECHNOLOGICAL, COMMERCIAL AND
USER PURPOSES, DRAFT INTERNATIONAL
STANDARDS MAY ON OCCASION HAVE TO
This document is circulated as received from the committee secretariat.
BE CONSIDERED IN THE LIGHT OF THEIR
POTENTIAL TO BECOME STANDARDS TO
WHICH REFERENCE MAY BE MADE IN
NATIONAL REGULATIONS.
RECIPIENTS OF THIS DRAFT ARE INVITED
TO SUBMIT, WITH THEIR COMMENTS,
NOTIFICATION OF ANY RELEVANT PATENT
RIGHTS OF WHICH THEY ARE AWARE AND TO
PROVIDE SUPPORTING DOCUMENTATION.
Reference number
ISO/DIS 17880:2024(en)
DRAFT
ISO/DIS 17880:2024(en)
International
Standard
ISO/DIS 17880
ISO/TC 61/SC 10
Cellular plastics — Self-supporting
Secretariat: SCC
metal faced sandwich panels
Voting begins on:
Plastiques — Panneaux sandwich à parements métalliques
autoportants
Voting terminates on:
ICS: 83.140.99
THIS DOCUMENT IS A DRAFT CIRCULATED
FOR COMMENTS AND APPROVAL. IT
IS THEREFORE SUBJECT TO CHANGE
AND MAY NOT BE REFERRED TO AS AN
INTERNATIONAL STANDARD UNTIL
PUBLISHED AS SUCH.
IN ADDITION TO THEIR EVALUATION AS
BEING ACCEPTABLE FOR INDUSTRIAL,
© ISO 2024
TECHNOLOGICAL, COMMERCIAL AND
USER PURPOSES, DRAFT INTERNATIONAL
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
STANDARDS MAY ON OCCASION HAVE TO
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
This document is circulated as received from the committee secretariat. BE CONSIDERED IN THE LIGHT OF THEIR
the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below
POTENTIAL TO BECOME STANDARDS TO
WHICH REFERENCE MAY BE MADE IN
or ISO’s member body in the country of the requester.
NATIONAL REGULATIONS.
ISO copyright office
RECIPIENTS OF THIS DRAFT ARE INVITED
CP 401 • Ch. de Blandonnet 8
TO SUBMIT, WITH THEIR COMMENTS,
CH-1214 Vernier, Geneva
NOTIFICATION OF ANY RELEVANT PATENT
Phone: [phone]
RIGHTS OF WHICH THEY ARE AWARE AND TO
PROVIDE SUPPORTING DOCUMENTATION.
Email: [e-mail]
Website: www.iso.org
Published in Switzerland Reference number
ISO/DIS 17880:2024(en)
ii
ISO/DIS 17880:2024(en)
Contents Page
Foreword .v
Introduction .vi
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 3
4 Symbols and abbreviated terms. 5
5 Requirements, properties and test methods . 8
5.1 Requirements for component materials .8
5.1.1 General .8
5.1.2 Metal facings .8
5.1.3 Core materials .10
5.1.4 Adhesives and bonding .10
5.2 Properties of sandwich panels .10
5.2.1 Mechanical resistance of the sandwich panel .10
5.2.2 Thermal transmittance . 12
5.2.3 Durability and other long-term effects . 12
5.2.4 Fire characteristics . 13
5.2.5 Dimensional tolerances for sandwich panels .14
5.2.6 Water permeability (optional characteristic) . 15
5.2.7 Air permeability . . 15
5.2.8 Water vapour permeability (optional characteristic) . 15
5.2.9 Airborne sound insulation (R (C;C )) (optional characteristic) . 15
w tr
5.2.10 Sound absorption (α ) (optional characteristic) . 15
w
5.3 Actions and safety level requirements . 15
5.3.1 Mechanical resistance to design loads . 15
5.3.2 Actions and combinations of actions .16
6 Testing, assessment and sampling methods .16
6.1 General .16
6.2 Type testing – TT .16
6.2.1 Initial type evaluation .16
6.2.2 Sampling for TT and audit testing purposes .16
6.2.3 Shortened testing programme – ITT (product change) . 20
6.3 Factory Production Control (FPC) .21
6.3.1 General .21
6.3.2 Results of FPC tests . 22
6.3.3 Equipment . 22
6.3.4 Raw materials and components . 23
6.3.5 Product testing and assessment – FPC . 23
6.3.6 Factory Production Control – supplier purchases . 26
6.4 Characteristic values from families of tests.27
7 Classification and designation .28
8 Marking, labelling and packaging .29
8.1 Marking and labelling . 29
8.2 Packaging, transport, storage and handling . 29
Annex A (normative) Testing procedures for material properties .30
Annex B (normative) Durability testing method for sandwich panels . 76
Annex C (informative) Fire tests .87
Annex D (normative) Dimensional tolerances . .101
Annex E (normative) Design procedures .110

iii
ISO/DIS 17880:2024(en)
Bibliography .131

iv
ISO/DIS 17880:2024(en)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out through
ISO technical committees. Each member body interested in a subject for which a technical committee
has been established has the right to be represented on that committee. International organizations,
governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely
with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are described
in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the different types
of ISO documents should be noted. This document was drafted in accordance with the editorial rules of the
ISO/IEC Directives, Part 2 (see www.iso.org/directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of any patent
rights identified during the development of the document will be in the Introduction and/or on the ISO list of
patent declarations received (see www.iso.org/patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation on the meaning of ISO specific terms and expressions related to conformity assessment,
as well as information about ISO's adherence to the World Trade Organization (WTO) principles in the
Technical Barriers to Trade (TBT) see the following URL: www.iso.org/iso/foreword.html.
The committee responsible for this document is ISO/TC 61, Plastics, Subcommittee SC 10, Cellular plastics.

v
ISO/DIS 17880:2024(en)
Introduction
This document has been developed with cellular plastics as the core, but this document has been modified to
include other materials such as mineral wool.

vi
DRAFT International Standard ISO/DIS 17880:2024(en)
Cellular plastics — Self-supporting metal faced sandwich panels
1 Scope
This document specifies requirements for factory made, self-supporting, double skin metal-faced insulating
sandwich panels where the insulating core materials are intended to be but not limited to cellular plastics
and mineral wool as defined below.
The sandwich panels are intended for discontinuous laying in the following applications:
a) roofs and roof cladding;
b) external walls and wall cladding.
The insulating core materials covered by this document are rigid polyurethane foam (PUR), polyisocyanurate
foam (PIR), expanded polystyrene foam (EPS), extruded polystyrene foam (XPS), phenolic foam (PF), and
mineral wool. Sandwich panels with edge details that utilize different materials from the main insulating
core are included in this document.
Sandwich panels used in outdoor cold storage applications are included in this document.
This document does not cover the following:
a) sandwich panels with a declared thermal conductivity for the insulating core material greater than
0,06 W/m K at 10 °C;
b) sandwich panels consisting of two or more clearly defined layers of different insulating core materials
(multi-layered);
c) sandwich panels with perforated facing(s);
d) curved sandwich panels;
e) indoor cold storage applications
The products covered by this Document shall be controlled by the manufacturer under system 1 of
ISO 12576-1. Its purpose is to provide uniform methods that are used to determine whether a production or a
consignment of a thermal insulating material should be accepted as conforming to the relevant specification
requirements.
System 1 of ISO 12576-1 defines the manufacturer's declaration of conformity, based on the manufacturer's
factory production control, based on ISO9001: 2000, without any participation of a third party.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content constitutes
requirements of this document. For dated references, only the edition cited applies. For undated references,
the latest edition of the referenced document (including any amendments) applies.
ISO 140-3, Acoustics — Measurement of sound insulation in buildings and of building elements — Part 3:
Laboratory measurements of airborne sound insulation of building elements
ISO 354, Acoustics — Measurement of sound absorption in a reverberation room
ISO 717-1, Acoustics — Rating of sound insulation in buildings and of building elements — Part 1: Airborne
sound insulation
ISO/DIS 17880:2024(en)
ISO 834-1, Fire-resistance tests — Elements of building construction — General requirements
ISO 834-3, Fire-resistance tests — Elements of building construction — Part 3: Commentary on test method and
guide to the application of the outputs from the fire-resistance test
ISO 834-4, Fire-resistance tests — Elements of building construction — Part 4: Specific requirements for
loadbearing vertical separating elements
ISO 834-5, Fire-resistance tests — Elements of building construction — Part 5: Specific requirements for
loadbearing horizontal separating elements
ISO 834-8, Fire-resistance tests — Elements of building construction — Part 8: Specific requirements for non-
loadbearing vertical separating elements
ISO 1182, Reaction to fire tests for products — Non-combustibility test
ISO 4898, Rigid cellular plastics — Thermal insulation products for buildings — Specifications
ISO 6270-1, Paints and varnishes — Determination of resistance to humidity — Part 1: Condensation (single-
sided exposure)
ISO 6361-2, Wrought aluminium and aluminium alloys — Sheets, strips and plates — Part 2: Mechanical
properties
ISO 6361-3, Wrought aluminium and aluminium alloys — Sheets, strips and plates — Part 3: Strips: Tolerances
on shape and dimensions
ISO 6892-1, Metallic materials — Tensile testing — Part 1: Method of test at room temperature
ISO 6946, Building components and building elements — Thermal resistance and thermal transmittance —
Calculation methods
ISO 9229, Thermal insulation — Vocabulary
ISO 9445-2, Continuously cold-rolled stainless steel — Tolerances on dimensions and form — Part 2: Wide strip
and plate/sheet
ISO 10211-1, Thermal bridges in building construction — Heat flows and surface temperatures — Part 1:
General calculation methods
ISO 10211-2, Thermal bridges in building construction — Calculation of heat flows and surface temperatures —
Part 2: Linear thermal bridges
ISO 10456, Building materials and products — Procedures for determining declared and design thermal values
ISO 11654, Acoustics — Sound absorbers for use in buildings — Rating of sound absorption
ISO 11925-2, Reaction to fire tests — Ignitability of products subjected to direct impingement of flame — Part 2:
Single-flame source test
ISO 12468-1, External exposure of roofs to fire — Part 1: Test method
ISO 12468-2, External exposure of roofs to fire — Part 2: Classification of roofs
ISO 12491, Statistical methods for quality control of building materials and components
ISO 13943, Fire safety — Vocabulary
ISO 13784-1, Reaction to fire test for sandwich panel building systems — Part 1: Small room test
ISO 13784-2, Reaction-to-fire tests for sandwich panel building systems — Part 2: Test method for large rooms
ISO 13785-1, Reaction-to-fire tests for façades — Part 1: Intermediate-scale test
ISO 13785-2, Reaction-to-fire tests for façades — Part 2: Large-scale test

ISO/DIS 17880:2024(en)
ISO 16163, Continuously hot-dipped coated steel sheet products — Dimensional and shape tolerances
ISO 16544, Thermal insulating products for building applications — Conditioning to moisture equilibrium under
specified temperature and humidity conditions
ISO 22111, Bases for design of structures — General requirements
ISO 29465, Thermal insulating products for building applications — Determination of length and width
ISO 29466, Thermal insulating products for building applications — Determination of thickness
ISO 29469, Thermal insulating products for building applications — Determination of compression behaviour
ISO 29470, Thermal insulating products for building applications — Determination of the apparent density
ISO 29765, Thermal insulating products for building applications — Determination of tensile strength
perpendicular to faces
EN 508-1, Roofing products from metal sheet — Specification for self-supporting products of steel, aluminium or
stainless steel sheet — Part 1: Steel
EN 826, Thermal insulating products for building applications — Determination of compression behaviour
EN 1172, Copper and copper alloys — Sheet and strip for building purposes
EN 1396, Aluminium and aluminium alloys — Coil coated sheet and strip for general applications — Specifications
EN 10088-1, Stainless steels — Part 1: List of stainless steels
EN 10143, Continuously hot-dip metal coated steel sheet and strip — Tolerances on dimensions and shape
EN 10169, Continuously organic coated (coil coated) steel flat products — Technical delivery conditions
EN 10346, Continuously hot-dip coated steel flat products for cold forming - Technical delivery conditions
EN 12865, Hygrothermal performance of building components and building elements — Determination of the
resistance of external wall systems to driving rain under pulsating air pressure
EN 13501-1, Fire classification of construction products and building elements — Part 1: Classification using
test data from reaction to fire tests
EN 14135, Coverings — Determination of fire protection ability
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 9229 and the following apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— IEC Electropedia: available at https:// www .electropedia .org/
— ISO Online browsing platform: available at https:// www .iso .org/ obp
3.1
auto-adhesion
self-adhesion of the core to the face(s) occurring automatically without the use of an adhesive
3.2
bending moment capacity,
maximum bending moment recorded during a test on an individual panel
3.3
bending resistance
characteristic value of bending moment capacity determined on the basis of a test series

ISO/DIS 17880:2024(en)
3.4
bond, bonding
adhesion between the face(s) and the core normally provided by an approved adhesive
3.5
core
layer of material, having thermal insulating properties, which is bonded between two metal faces, creating
a sandwich panel
3.6
durability
ability of the panel to withstand the environmental effects and accommodate the consequent decrease in
mechanical strength with time caused by factors such as temperature, humidity, freeze-thaw cycles and
their various combinations
3.7
edge, longitudinal edge
side of the panel where adjacent panels join together in the same plane
3.8
face, facing
flat, lightly profiled or profiled thin metal sheet firmly bonded to the core
3.9
flat facing
facing without any rolled or pressed profile, or raised strengthening rib
3.10
incompletely bonded face
metal face whose bond to the core is adequate for sandwich action but does not include the entire surface of
the core
Note 1 to entry: An example is a trapezoidally profiled face that has voids between the raised profiles and the core.
3.11
incompletely bonded panel
panel in which one or both faces is incompletely bonded
3.12
joint
interface between two panels where the meeting edges have been designed to allow the panels to join
together in the same plane
Note 1 to entry: The joint may incorporate interlocking parts that enhance the mechanical properties of the system as
well as improving the thermal, acoustic and fire performance and restricting air movement.
Note 2 to entry: The term 'joint' does not refer to a junction between cut panels or a junction where the panels are not
installed in the same plane.
3.13
lamella
core material consisting of mineral wool that has been cut and orientated with the fibres perpendicular to
the facings prior to bonding
3.14
lightly profiled facing
facing with a rolled or pressed profile not exceeding 5 mm in depth
3.15
pre-manufactured, pre-formed
component or material that is supplied to the manufacturer ready for direct incorporation into the sandwich
panel as a core
ISO/DIS 17880:2024(en)
3.16
sandwich panel
building product consisting of two metal faces positioned on either side of a core that is a thermally
insulating material, which is firmly bonded to both faces so that the three components act compositely when
under load
3.17
self-supporting panel
panel capable of supporting, by virtue of its materials and shape, its self-weight and in the case of panels fixed
to spaced structural supports all applied loadings (e.g. snow, wind, internal air pressure), and transmitting
these loadings to the supports
3.18
shift
period of production during a working day, normally 6 h to 8 h but can be less
3.19
side lap
folded area of one or both facing materials along the longitudinal edge of the panel which engages with the
adjacent panel to form an interlocking or overlapping joint
3.20
wrinkling strength
the characteristic value of wrinkling stress
3.21
wrinkling stress
the stress in the compressed face of a panel undergoing failure in bending, where the failure mode takes the
form of a "wrinkle" extending over the full width of the panel near the section of maximum bending moment
4 Symbols and abbreviated terms
For the purposes of this document, the following symbols and abbreviations apply.
A cross-sectional area (may be full width of panel or per unit width)
B flexural rigidity (may be full width of panel or per unit width), overall width of the panel/specimen
C ratio
D overall depth of the panel
E modulus of elasticity
F force, load, support reaction
G shear modulus, permanent action
I moment of inertia
L span, distance, width of support (L )
s
M bending moment
N axial compressive force
Q variable action
R resistance, sound reduction index (R ), reflectivity (R ), tensile strength (R , R )
w G DUR 24
ISO/DIS 17880:2024(en)
S shear rigidity, value of a load effect, effect of an action
T temperature
U thermal transmittance, thermal transmittance including the influence of the joints U
d,s
V shear force
a distance apart of clips
b width of test specimen, width of plate, width of ribs/valleys, bowing
d depth of face profile or stiffeners, depth of core (d )
c
e distance between centroids of faces, base of natural logarithms (e = 2,718 282)
f strength, yield stress, thermal transmittance contribution factor ( f )
joint
h height of profile, thickness (e.g. glue)
k correction factor
l length, deviation
m mass
n number of tests, number of screws, number of webs
p pitch of profile
q live load
r radius
s length of web (s )
w1
t thickness of face sheet
v variance factor
w deflection, displacement, compression, cover width
x, y, z coordinates
α coefficient of thermal expansion, sound absorption (α )
w
β design parameter
δ deviation
φ angle
γ shear strain, partial safety factor
λ thermal conductivity, λ (design value)
Design
φ creep coefficient
θ design parameter
σ stress, compressive strength σ , standard deviation
m
ISO/DIS 17880:2024(en)
τ shear stress
Ψ combination coefficient, linear thermal transmittance of joints
ρ coefficient, density
Subscripts
C core
D declared value (R )
D
F face, action ( γ )
F
G self-weight, degree
M material (γ )
M
Q variable action
S sandwich part of the cross-section
adj adjusted
b bending, elastic extension
c compression, core, carrier, clip ( f )
joint,c
d design
e external, additional thickness of main profiles (Δe)
eff effective
f load, facing (λ )
fi
i internal (λ )
fi
i, j index
k characteristic value
lin linear
m material
n nominal
nc without clip ( f )
joint,nc
obs observed (e.g. result)
q uniform load
s support (L = support width), stiffeners, surface (R )
s s1
t tension, time
tol tolerance (normal or special)
tr traffic (C )
tr
ISO/DIS 17880:2024(en)
u ultimate (F )
u
v shear, variance
w wind, web, wrinkling (σ ), weighted (R )
w w
y yield
0 basic value, unit width, time (e.g. t = 0)
1 external face, upper face
2 internal face, lower face
Abbreviations
CG cellular glass
EPS expanded polystyrene
FPC factory production control
TT type test
NPD no performance determined
PCS gross calorific potential
PUR rigid polyurethane foam (the abbreviation PUR includes polyisocyanurate foam (PIR))
PF phenolic foam
XPS extruded polystyrene foam
5 Requirements, properties and test methods
5.1 Requirements for component materials
5.1.1 General
The product shall be manufactured with materials and components conforming to 5.1.2 to 5.1.4.
5.1.2 Metal facings
5.1.2.1 Steel
5.1.2.1.1 Steel faces
Steel faces (other than stainless steel) shall have minimum yield strength of 220 N/mm and shall conform
to the requirements of the appropriate standard given in Table 1.
For steels according to Table 1, the steel grade, nominal thickness and tolerance system of each face shall be
declared. Tolerances on thickness shall be according to the ―special or ―normal tolerances as described in
the relevant standards.
ISO/DIS 17880:2024(en)
Table 1 — Standards for steel with metallic coating
Metallic coating Standard
Zinc, Zinc-Magnesium, 5 % Al-Zn, 55 % Al-Zn and Alumin-
EN 10346
ium-silicon
Differential zinc coating shall be permitted for the external face of a panel exposed to the climate for all core materials.
Organic protective coatings shall be selected according to their durability in the application environment.
Organic coated steel sheets shall conform to the requirements of EN 10169. Multi-layer coatings shall
conform to EN 508-1.
The panel manufacturer shall state the metal grade, thickness and tolerance system of each face. Tolerances
on thickness shall be according to “special” or “normal” tolerances as described in the relevant standards.
The thickness of steel facing sheets shall be determined in accordance with ISO 16163.
NOTE Not all steels in Table 1 are suitable for sandwich panels in all the intended end uses.
5.1.2.1.2 Back face coating
If the metal face is bonded over its whole area to a rigid foam core with a closed cell structure, the reverse
side metallic coating mass shall be a minimum of 50 g/m .
When relevant to intended end use application, resistance of metallic protective coatings and organic back
face coat (duplex coating) against corrosion shall be ensured by laboratory tests. Minimum resistance of
backing coat shall be CPI2 according to EN 10169. Additionally, to the requirements in EN 10169 only slight
colour change (DE ≤ 2,0) shall be acceptable in the condensation-water test (ISO 6270-1) over 1 000 h.
NOTE The requirements in 5.1.2.1.2 are only applicable to back face coatings.
5.1.2.2 Stainless steel faces
Stainless steel facings shall have a minimum yield strength of 220 N/mm . The chemical composition of
stainless steel faces and their physical properties shall conform to EN 10088-1.
The panel manufacturer shall state the metal grade, thickness and tolerance system of each face. Tolerances
on thickness shall be according to “special” or “normal” tolerances as described in the relevant standards.
The thickness of stainless steel facing sheets shall be determined in accordance with ISO 9445-2.
NOTE Not all stainless steels in EN 10088–1 are suitable for sandwich panels in all the intended end uses.
Reference can be made to EN 508–3, grades suitable for roofing.
5.1.2.3 Aluminium faces
Aluminium facings shall have a design value of the stress at the 0,2 %-strain limit β (for simplification
0,2
called “yield strength“) of 140 N/mm . The chemical composition, temper and mechanical properties of
aluminium shall conform to ISO 6361-2.
Organic coated aluminium sheets shall conform to the requirements of EN 1396.
The panel manufacturer shall state the metal grade, thickness and tolerance system of each face. Tolerances
on thickness shall be according to “special” or “normal” tolerances as described in the relevant standards.
The thickness of aluminium facing sheets shall be determined in accordance with ISO 6361-3.
NOTE Not all aluminium alloys covered by EN 485–2 or EN 1396 are suitable for sandwich panels in all the
intended end uses. Reference can be made to EN 508–2.

ISO/DIS 17880:2024(en)
5.1.2.4 Copper faces
Copper facings shall have a design value of the stress at the 0,2 %-strain limit β (for simplification called
0,2
“yield strength“) of 180 N/mm . The chemical composition, temper, mechanical properties and thickness
tolerances of copper faces shall conform to EN 1172.
NOTE Only R240 and R290 grades in EN 1172 satisfy the requirement of 180 N/mm .
The panel manufacturer shall state the metal grade, thickness and tolerance system of each face. Tolerances
on thickness shall be according to “special” or “normal” tolerances as described in the relevant standards.
The thickness of copper facing sheets shall be determined in accordance with EN 1172.
5.1.3 Core materials
5.1.3.1 Thermal performance
The declared and design thermal conductivity of core materials shall be determined in accordance with 5.2.2.
5.1.3.2 Thermal stability of core materials
The thermal stability of the core materials in a sandwich panel shall be evaluated through the durability
testing in accordance with 5.2.3
5.1.4 Adhesives and bonding
Adhesives and bonding shall conform to 5.2.1.6 and 5.2.3.1.
The adhesion between the core and the faces of the sandwich panel has a fundamental role in the satisfactory
performance of the sandwich panel. The surface preparation of the facing material shall be appropriate for
the adhesive or the method of adhesion.
5.2 Properties of sandwich panels
5.2.1 Mechanical resistance of the sandwich panel
5.2.1.1 General
For mechanical properties, unless stated otherwise, the mean value and the characteristic value (5 % fractile
value assuming a confidence level of 75 % for each population of test results) shall be determined according
to ISO 12491.
Declared values shall be given to either two or three significant figures.
5.2.1.2 Shear strength (f ) and shear modulus (G )
Cv c
The declared values of the shear strength and shear modulus of the core shall be determined using the
appropriate test procedures from A.3 or A.4 in accordance with Table 2. The same test procedure shall be
used to determine both the shear strength and shear modulus of a panel. In principle, each test method is
suitable for panels with flat, lightly profiled or profiled facings.
The declared value of the shear strength shall be less than or equal to the characteristic value and shall be
declared by the manufacturer in megapascals (MPa).
Only the mean value of the shear modulus obtained from the available test results shall be declared. The
5 %-fractile value shall be recorded for FPC purposes in accordance with A.3 or A.4.

ISO/DIS 17880:2024(en)
Table 2 — Alternative shear test methods
Test procedure Core and face mate- Equation for evaluation Comments
rials
Shear strength Shear modulus
A.3 – 2 load points All core and face ma- A.5 A.7 Basic procedure. May
terials be used in all situa-
(on small sample)
tions unless practical
requirements dictate
otherwise.
A.4 – 2 load points All core materials. A.10 A.7 Alternative to A.3.
(on full panel) Flat or lightly profiled For panels with one
faces or two profiled faces
wrinkling of the faces
One or both faces A.12 A.11
may occur
profiled
A.4 – Vacuum cham- All core materials. A.10 A.13 Alternative to the use
ber or air bag loading of 2 load points.
Flat  or
lightly
profiled faces
One or both faces A.15 A.14
profiled
5.2.1.3 Creep coefficient(φ )
t
The creep coefficient shall be determined according to A.6 and expressed as a number.
The creep coefficient shall be determined for all sandwich panels used as a roof designed to carry long term
or permanent loads e.g. snow and self-weight.
5.2.1.4 Compressive strength (σ ) or compressive stress (σ )
m 10
The compressive strength of the core σ or its compressive stress at 10 % deformation σ (whichever is
m 10
reached first) shall be determined in accordance with the method given in A.2 and shall be declared by the
manufacturer in megapascals (MPa).
5.2.1.5 Shear strength after long-term loading (f long-term)
Cv
The shear strength after long term loading shall be determined in accordance with A.3.6. This value shall be
determined for all sandwich panels used as a roof designed to carry long term or permanent loads e.g. snow
and self-weight. The declared value shall be less than or equal to the characteristic value ( f ) and shall be
Cv
declared by the manufacturer in megapascals (MPa).
NOTE The reduction obtained from the small-scale long-term test can be applied to panels where the shear
strength has been determined on the basis of large-scale tests to A.4 or calculated on the basis of A.3.5.3.
5.2.1.6 Cross panel tensile strength (f )
Ct
The characteristic value for tensile strength and cross panel tensile strength perpendicular to the panel
faces shall be greater than 0,018 MPa when tested in accordance with A.1 and shall be declared by the
manufacturer in megapascals (MPa).
The declared values shall be less than or equal to the characteristic value.
NOTE Low tensile strength can reduce the wrinkling strength and increase its variability. Account is taken of this
in A.5.5.5 (k factor).
5.2.1.7 Bending moment capacity (M) and wrinkling stress (σ )
u w
The bending moment capacity shall be obtained by testing according to A.5

ISO/DIS 17880:2024(en)
For panels with flat, lightly profiled or profiled faces, the wrinkling stress shall be calculated in accordance
with A.5.5 and the wrinkling strength shall be declared by the manufacturer in megapascals (MPa).
The declared wrinkling stress should generally be determined on the basis of the results of bending tests.
However, A.5.5.3 also allows a conservative value of the wrinkling stress to be calculated according to
Equation A.20 and declared.
Wrinkling stress is related to bending moment by a simple mathematical relationship so that it is not
necessary to declare both the bending resistance and the wrinkling strength.
For a panel with a profiled face in compression, the bending resistance shall be declared together with the
span of the test specimen. Optionally the wrinkling stress can be declared.
If it is intended that design shall be carried out on the basis of calculations in accordance with Annex E, it is
preferable to declare the wrinkling strength wherever possible.
NOTE Declaration of the bending moment is essential for design on the basis of testing.
5.2.1.8 Bending moment capacity and wrinkling stress over a central support
The bending moment capacity over a central support shall be determined in accordance with A.7. For
sandwich panels with flat or lightly profiled faces, the wrinkling stress shall then be calculated in accordance
with A.5.5.
The bending moment capacity over a central support is required when sandwich panels which are
continuous over two or more spans are to be designed by calculation in accordance with Annex E. In such
cases, the comparison of the design values of resistance according to E.2 is usually carried out in terms of
stresses. If the sandwich panel has one or more profiled faces, the determination of the ultimate compressive
(wrinkling) stress from the bending moment capacity requires calculation in accordance with E.7.5. It is
recommended that this calculation is carried out at the time of testing.
5.2.2 Thermal transmittance
The thermal transmittance value for the panel (U), incorporating the manufacturer’s declared thermal
conductivity for the core material (λ ) and the joints and any profiled facings, shall be determined in
Declared
accordance with A.11.
Both λ and the U -value shall be declared.
Declared d,s
5.2.3 Durability and other long-term effects
5.2.3.1 Reduction of tensile strength with time as a consequence of ageing (durability)
Sandwich panels shall satisfy the criteria for reduction in tensile strength in accordance with the relevant
test method DUR1 and DUR2 (see Table 3) as described in Annex B.
Durability tests shall be applied to sandwich panels designed for external applications. They are based on
the accelerated ageing effect of temperature or humidity, which from long-term experience are critical for
each core material.
The durability tests may be used to assess the performance of internal sandwich panels.
NOTE 1 These tests evaluate the reduction of tensile strength as a result of temperature or humidity on a pass/fail basis.
NOTE 2 The durability requirement covers the performance of all essential structural components of the panel, for
example backface coatings, adhesion layers and core material.
PUR sandwich panels manufactured using the blowing agents covered within ISO 4898 and a combination
of these blowing agents, but excluding CO blown foams shall be considered to satisfy the durability
requirements without testing. PUR sandwich panels manufactured with other blowing agents shall be
tested according to test DUR1 and the colour reflectivity levels shall be declared (B.2.5).

ISO/DIS 17880:2024(en)
Table 3 — Durability tests and deemed to satisfy criteria
Insulating core material Test method (Annex B) Note
Polystyrene (EPS or XPS) DUR1 DUR1 including wedge test (B.5)
No test required for sandwich panels manufactured
Polyurethane (PUR), – using the blowing agents covered within ISO 4898, but
DUR1
excluding foams blown solely by CO
auto-adhesive bond 2
Other blowing agents shall be tested to DUR1
No test required for sandwich panels manufactured
using the blowing agents covered within ISO 4898, but
excluding CO blown foams.
Polyurethane (PUR), –
DUR1
Other blowing agents shall be tested to DUR1 including
adhesive bond
the wedge test (B.4)
The wedge test (B.4) shall be carried out
DUR1, thermal shock B.6 and PF sandwich panels with an adhesive bond shall be tested
Phenolic (PF)
repeated loading B.5 to DUR1 including the wedge test (B.4)
Mineral Wool (MW) DUR2 DUR2 including the wedge test (B.5)
5.2.3.2 Resistance to point loads and access loads –roof sandwich panels
The ability of a sandwich panel to resist point loads and access loads shall be determined in accordance with
A.10.1. For applications where there will be more frequent access than occasional foot traffic (see NOTE), the
procedure described in A.10.2 shall also be carried out.
NOTE 1 Point loads are loads resulting from a single person walking on the panel, for occasional access both during
and after erection.
5.2.4 Fire characteristics
5.2.4.1 Reaction to fire
The reaction to fire of sandwich panels shall be determined according to ISO 13784-1
...

FINAL DRAFT
International
Standard
ISO/TC 61/SC 10
Cellular plastics — Self-supporting
Secretariat: SCC
metal faced sandwich panels
Voting begins on:
Plastiques alvéolaires — Panneaux sandwich à parements 2026-05-11
métalliques autoportants
Voting terminates on:
2026-07-06
RECIPIENTS OF THIS DRAFT ARE INVITED TO SUBMIT,
WITH THEIR COMMENTS, NOTIFICATION OF ANY
RELEVANT PATENT RIGHTS OF WHICH THEY ARE AWARE
AND TO PROVIDE SUPPOR TING DOCUMENTATION.
IN ADDITION TO THEIR EVALUATION AS
BEING ACCEPTABLE FOR INDUSTRIAL, TECHNO­
LOGICAL, COMMERCIAL AND USER PURPOSES, DRAFT
INTERNATIONAL STANDARDS MAY ON OCCASION HAVE
TO BE CONSIDERED IN THE LIGHT OF THEIR POTENTIAL
TO BECOME STAN DARDS TO WHICH REFERENCE MAY BE
MADE IN NATIONAL REGULATIONS.
Reference number
FINAL DRAFT
International
Standard
ISO/TC 61/SC 10
Cellular plastics — Self-supporting
Secretariat: SCC
metal faced sandwich panels
Voting begins on:
Plastiques alvéolaires — Panneaux sandwich à parements
métalliques autoportants
Voting terminates on:
RECIPIENTS OF THIS DRAFT ARE INVITED TO SUBMIT,
WITH THEIR COMMENTS, NOTIFICATION OF ANY
RELEVANT PATENT RIGHTS OF WHICH THEY ARE AWARE
AND TO PROVIDE SUPPOR TING DOCUMENTATION.
© ISO 2026
IN ADDITION TO THEIR EVALUATION AS
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
BEING ACCEPTABLE FOR INDUSTRIAL, TECHNO­
LOGICAL, COMMERCIAL AND USER PURPOSES, DRAFT
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
INTERNATIONAL STANDARDS MAY ON OCCASION HAVE
the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below
TO BE CONSIDERED IN THE LIGHT OF THEIR POTENTIAL
or ISO’s member body in the country of the requester.
TO BECOME STAN DARDS TO WHICH REFERENCE MAY BE
MADE IN NATIONAL REGULATIONS.
ISO copyright office
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Published in Switzerland Reference number
ii
Contents Page
Foreword .v
Introduction .vi
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 3
4 Symbols and abbreviated terms. 5
4.1 Symbols .5
4.2 Abbreviated terms .10
5 Requirements, properties and test methods .11
5.1 Requirements for component materials .11
5.1.1 General .11
5.1.2 Metal facings .11
5.1.3 Core materials . 12
5.1.4 Adhesives and bonding . 12
5.2 Properties of sandwich panels . 13
5.2.1 Mechanical resistance of the sandwich panel . 13
5.2.2 Thermal transmittance . 15
5.2.3 Durability and other long-term effects . 15
5.2.4 Fire characteristics .16
5.2.5 Dimensional tolerances for sandwich panels .16
5.2.6 Water permeability (optional characteristic) .17
5.2.7 Air permeability . .17
5.2.8 Water vapour permeability (optional characteristic) .18
5.2.9 Airborne sound insulation (R (C;C )) (optional characteristic) .18
w tr
5.2.10 Sound absorption (α ) (optional characteristic) .18
w
5.3 Actions and safety level requirements .18
6 Testing, assessment and sampling methods .18
6.1 General .18
6.2 Type testing – TT .19
6.2.1 Initial type evaluation .19
6.2.2 Sampling for TT and audit testing purposes .19
6.2.3 Shortened testing programme — ITT (product change) . 22
6.3 Factory production control (FPC) . 23
6.3.1 General . 23
6.3.2 Results of FPC tests .24
6.3.3 Equipment .24
6.3.4 Raw materials and components . 25
6.3.5 Product testing and assessment . 26
6.3.6 Supplier purchases . 28
6.4 Characteristic values from families of tests. 29
7 Classification and designation .30
8 Marking, labelling and packaging .31
8.1 Marking and labelling .31
8.2 Packaging, transport, storage and handling .31
Annex A (normative) Testing procedures for material properties .32
Annex B (normative) Durability testing method for sandwich panels .75
Annex C (informative) Fire tests .87
Annex D (normative) Dimensional tolerances . .101
Annex E (informative) Design procedures .112

iii
Bibliography .131

iv
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out through
ISO technical committees. Each member body interested in a subject for which a technical committee
has been established has the right to be represented on that committee. International organizations,
governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely
with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are described
in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the different types
of ISO document should be noted. This document was drafted in accordance with the editorial rules of the
ISO/IEC Directives, Part 2 (see www.iso.org/directives).
ISO draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). ISO takes no position concerning the evidence, validity or applicability of any claimed patent
rights in respect thereof. As of the date of publication of this document, ISO had not received notice of (a)
patent(s) which may be required to implement this document. However, implementers are cautioned that
this may not represent the latest information, which may be obtained from the patent database available at
www.iso.org/patents. ISO shall not be held responsible for identifying any or all such patent rights.
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and expressions
related to conformity assessment, as well as information about ISO's adherence to the World Trade
Organization (WTO) principles in the Technical Barriers to Trade (TBT), see www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 61, Plastics, Subcommittee SC 10, Cellular
plastics.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.

v
Introduction
This document has been developed with cellular plastics as the core. It has been eventually modified to
include other materials, such as mineral wool.

vi
FINAL DRAFT International Standard ISO/FDIS 17880:2026(en)
Cellular plastics — Self-supporting metal faced sandwich
panels
1 Scope
This document specifies requirements for factory made, self-supporting, double skin metal-faced insulating
sandwich panels where the insulating core materials are intended to be but not limited to cellular plastics
and mineral wool as defined below.
The sandwich panels are intended for discontinuous laying in the following applications:
a) roofs and roof cladding;
b) external walls and wall cladding.
The insulating core materials covered by this document are rigid polyurethane foam (PUR), polyisocyanurate
foam (PIR), expanded polystyrene foam (EPS), extruded polystyrene foam (XPS), phenolic foam (PF) and
mineral wool. Sandwich panels with edge details that utilize different materials from the main insulating
core are included in this document. Sandwich panels used in outdoor cold storage applications are included
in this document.
This document does not cover the following:
— sandwich panels with a declared thermal conductivity for the insulating core material greater than
0,06 W/mK at 10 °C, or greater than 0,06 W/mK at 23 °C;
— sandwich panels consisting of two or more clearly defined layers of different insulating core materials
(multi-layered);
— sandwich panels consisting of more than one metal sheet per face;
— sandwich panels with perforated facing(s);
— curved sandwich panels;
— indoor cold storage applications.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content constitutes
requirements of this document. For dated references, only the edition cited applies. For undated references,
the latest edition of the referenced document (including any amendments) applies.
ISO 354:2003, Acoustics — Measurement of sound absorption in a reverberation room
ISO 717-1, Acoustics — Rating of sound insulation in buildings and of building elements — Part 1: Airborne
sound insulation
ISO 834-1, Fire-resistance tests — Elements of building construction — Part 1: General requirements
ISO 834-4, Fire-resistance tests — Elements of building construction — Part 4: Specific requirements for
loadbearing vertical separating elements
ISO 834-5, Fire-resistance tests — Elements of building construction — Part 5: Specific requirements for
loadbearing horizontal separating elements

ISO 834-8, Fire-resistance tests — Elements of building construction — Part 8: Specific requirements for non-
loadbearing vertical separating elements
ISO 834-9, Fire-resistance tests — Elements of building construction — Part 9: Specific requirements for non-
loadbearing ceiling elements
ISO 845, Cellular plastics and rubbers — Determination of apparent density
ISO 1182, Reaction to fire tests for products — Non-combustibility test
ISO 4898, Rigid cellular plastics — Thermal insulation products for buildings — Specifications
ISO 6270-1, Paints and varnishes — Determination of resistance to humidity — Part 1: Condensation (single-
sided exposure)
ISO 6361-2, Wrought aluminium and aluminium alloys — Sheets, strips and plates — Part 2: Mechanical
properties
ISO 6361-3, Wrought aluminium and aluminium alloys — Sheets, strips and plates — Part 3: Strips: Tolerances
on shape and dimensions
ISO 6892-1, Metallic materials — Tensile testing — Part 1: Method of test at room temperature
ISO 6946, Building components and building elements — Thermal resistance and thermal transmittance —
Calculation methods
ISO 8145, Thermal insulation; mineral wool board for overdeck insulation of roofs — Specification
ISO 8301, Thermal insulation — Determination of steady-state thermal resistance and related properties —
Heat flow meter apparatus
ISO 8302, Thermal insulation — Determination of steady-state thermal resistance and related properties —
Guarded hot plate apparatus
ISO 9229, Thermal insulation — Vocabulary
ISO 9445-2:2009, Continuously cold-rolled stainless steel — Tolerances on dimensions and form — Part 2: Wide
strip and plate/sheet
ISO 10140-1:2021, Acoustics — Laboratory measurement of sound insulation of building elements — Part 1:
Application rules for specific products
ISO 10140-2:2021, Acoustics — Laboratory measurement of sound insulation of building elements — Part 2:
Measurement of airborne sound insulation
ISO 10211, Thermal bridges in building construction — Heat flows and surface temperatures — Detailed
calculations
ISO 10456, Building materials and products — Hygrothermal properties — Tabulated design values and
procedures for determining declared and design thermal values
ISO 11654, Acoustics — Sound absorbers for use in buildings — Rating of sound absorption
ISO 11925-2, Reaction to fire tests — Ignitability of products subjected to direct impingement of flame — Part 2:
Single-flame source test
ISO 12468-1, External exposure of roofs to fire — Part 1: Test method
ISO/TR 12468-3, External exposure of roofs to fire — Part 3: Commentary
ISO 12491, Statistical methods for quality control of building materials and components
ISO 13784-1:2014, Reaction to fire test for sandwich panel building systems — Part 1: Small room test

ISO 13784-2:2020, Reaction-to-fire tests for sandwich panel building systems — Part 2: Test method for large
rooms
ISO 13785-1, Reaction-to-fire tests for façades — Part 1: Intermediate-scale test
ISO 13785-2, Reaction-to-fire tests for façades — Part 2: Large-scale test
ISO 13943, Fire safety — Vocabulary
ISO 16163, Continuously hot-dipped coated steel sheet products — Dimensional and shape tolerances
ISO 22111, Bases for design of structures — General requirements
ISO 29465, Thermal insulating products for building applications — Determination of length and width
ISO 29466, Thermal insulating products for building applications — Determination of thickness
ISO 29469, Thermal insulating products for building applications — Determination of compression behaviour
ISO 29470, Thermal insulating products for building applications — Determination of the apparent density
ISO 29765, Thermal insulating products for building applications — Determination of tensile strength
perpendicular to faces
EN 508-1, Roofing products from metal sheet — Specification for self-supporting products of steel, aluminium or
stainless steel sheet — Part 1: Steel
EN 1172, Copper and copper alloys — Sheet and strip for building purposes
EN 1396, Aluminium and aluminium alloys — Coil coated sheet and strip for general applications — Specifications
EN 1990:2002 + A1: 2005 + A1: 2005/ AC: 2010, Eurocode - Basis of structural design
EN 10088-1, Stainless steels — Part 1: List of stainless steels
EN 10143:2006, Continuously hot-dip metal coated steel sheet and strip — Tolerances on dimensions and shape
EN 10169, Continuously organic coated (coil coated) steel flat products — Technical delivery conditions
EN 10204, Metallic products - Types of inspection documents
EN 12865, Hygrothermal performance of building components and building elements — Determination of the
resistance of external wall systems to driving rain under pulsating air pressure
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 9229, ISO 13943 and the following
apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
3.1
auto-adhesive bond
self-adhesion of the core to the face(s) occurring automatically without the use of an adhesive
Note 1 to entry: This technique is used for producing sandwich panels by foaming.
3.2
bending moment capacity
maximum bending moment recorded during a test on an individual panel

3.3
bending resistance
characteristic value of bending moment capacity determined on the basis of a test series
3.4
bond
bonding
adhesion between the face(s) and the core normally provided by an approved adhesive
3.5
core
layer of material, having thermal insulating properties, which is bonded between two metal faces, creating
a sandwich panel
3.6
durability
ability of the panel to withstand the environmental effects and accommodate the consequent decrease in
mechanical strength with time caused by factors such as temperature, humidity, freeze-thaw cycles and
their various combinations
3.7
edge
longitudinal edge
side of the panel where adjacent panels join together in the same plane
3.8
face
facing
flat, lightly profiled or profiled thin metal sheet firmly bonded to the core
3.9
flat face
face without any rolled or pressed profile or raised strengthening rib
3.10
lightly profiled face
face with a rolled or pressed profile not exceeding 5 mm in depth
3.11
profiled face
face with a rolled or pressed profile exceeding 5 mm in depth
3.12
incompletely bonded panel
panel in which one or both faces is incompletely bonded
3.13
joint
interface between two panels where the meeting edges have been designed to allow the panels to join
together in the same plane
Note 1 to entry: The joint can incorporate interlocking parts that enhance the mechanical properties of the system as
well as improving the thermal, acoustic and fire performance and restricting air movement.
Note 2 to entry: The term 'joint' does not refer to a junction between cut panels or a junction where the panels are not
installed in the same plane.
3.14
lamella
core material consisting of mineral wool that has been cut and orientated with the fibres perpendicular to
the facings prior to bonding
3.15
lightly profiled facing
facing with a rolled or pressed profile not exceeding 5 mm in depth
3.16
pre-manufactured
pre-formed
component or material that is supplied to the manufacturer ready for direct incorporation into the sandwich
panel as a core
3.17
sandwich panel
building product consisting of two metal faces positioned on either side of a core that is a thermally
insulating material, which is firmly bonded to both faces so that the three components act compositely when
under load
3.18
self-supporting sandwich panel
panel capable of supporting, by virtue of its materials and shape, its self-weight and in the case of panels fixed
to spaced structural supports all applied loadings (e.g. snow, wind, internal air pressure), and transmitting
these loadings to the supports
3.19
shift
period of production during a working day, normally 6 h to 8 h but can be less
3.20
side lap
folded area of one or both facing materials along the longitudinal edge of the panel which engages with the
adjacent panel to form an interlocking or overlapping joint
3.21
wrinkling strength
characteristic value of wrinkling stress (3.21)
3.22
wrinkling stress
stress in the compressed face of a panel undergoing failure in bending, where the failure mode takes the
form of a "wrinkle" extending over the full width of the panel near the section of maximum bending moment
4 Symbols and abbreviated terms
4.1 Symbols
For the purposes of this document, the following symbols and abbreviated terms apply.
A cross-sectional area of the specimen determined from the measured dimensions
A cross sectional area of the core based on measured depth d
C c
A area of the carrier
c
A measured area of cross-section of the top face based on measured metal thickness;
F1
A measured area of cross-section of the bottom face based on measured metal thickness;
F2
A area of facing sheet in square metres (m2)
glue
B bending stiffness, overall width of the panel/specimen

B minimum width of uncut core material across a line of cut ends
min
B bending stiffness with t and e
obs obs obs
B flexural rigidity
S
C ratio, design value of a serviceability criterion
C limiting design value of the relevant serviceability criterion expressed as the maximum service-
d
ability limit state design stress or limit on deflection taking into account the material partial
factor for serviceability limit state design γ
M
C spectrum adaptation term calculated with A-weighted urban traffic noise
tr
D overall depth of the panel
E modulus of elasticity, design value of the effect of an action
E mean of the characteristic values of the tensile and compressive moduli of the core material
C
E compressive E-modulus of the core
Cc
E tensile E-modulus of the core
Ct
E E-modulus of the top face
F1
E E-modulus of the bottom face
F2
F force, load, support reaction
F self-weight of the panel
G
F load at the end of the linear part of the load-deflection curve
lin
F test value of reaction capacity
Ri
F ultimate load
u
G shear modulus, permanent action
G shear modulus of the core
C
G reduced shear modulus of the core
C, red
G characteristic value of the permanent action
k
I moment of inertia
I moment of inertia of the profiled face(s) (sum if both faces are profiled)
F
I moment of inertia of the sandwich part (see Annex E)
S
L span, distance,
L width of support plate
s
M bending moment
M M Bending moments at ultimate limit state to determine σ
Du Su yr
M bending moment capacity
u
N axial compressive force
Q variable action
Q characteristic value of the dominant variable action
k1
Q characteristic value of the non-dominant variable action i (I > 1)
ki
R resistance
R test result modified to correspond to the design values of metal thickness
adj,i
R , R tensile strength
DUR 24
R degree of reflection relative to magnesium oxide = 100 %
G
R characteristic resistance
k
R result of test number I
obs,i
R external surface resistance (m K/W)
se
R internal surface resistance (m K/W)
si
R sound reduction index
w
S shear rigidity, value of a load effect, characteristic value of an action
S characteristic value of an action
ki
T temperature
U thermal transmittance value of the panel,
U thermal transmittance value of the panel including the influence of the panel joints
d,s
V shear force
a distance apart of clips
b width of test specimen, width of plate, width of ribs/valleys, bowing
b width of the clips
c
d depth of face profile or stiffeners,
d nominal thickness of the core (ignoring the thickness of the facings) and the geometry of the main
C
profiles), see Figure A.18 and Figure A.19
d design thickness of the panel
d
d depth of stiffeners
S
e distance between centroids of faces, base of natural logarithms (e = 2,718 282)
e additional thickness of the external face
e
e additional thickness of the internal face
i
e distance between the faces on basis of measured geometry
obs
f strength, yield stress , reduction factor

f mean compressive strength of the core
C
f compressive strength of the core
Cc
f cross panel tensile strength after time t
Ct
f shear strength of the core
Cv
f reduced shear strength of the core
Cv, red
f thermal transmittance contribution factor
joint
f thermal transmittance contribution factor with clip
joint, c
f thermal transmittance contribution factor without (no) clip
joint, nc
f design yield stress
y
f measured yield stress
y,obs
h height of profile
h thickness of adhesive in millimetres (mm)
glue
k correction factor, distribution parameter
k reduction factor for cut ends in pre-formed cores
v
l length, deviation
m mass
m amount of adhesive in grams per square metre (g/m ) from measurements during production
adhesive
m mass of the carrier
c
m mass of the carrier and adhesive
a+c
m amount of adhesive in grams per square metre (g/m ) from measurements on a manufactured
glue
panel
m mass of facing + glue in grams (g)
m mass of facing in grams (g)
n number of tests, number of screws, number of webs
p pitch of profile
q live load
r radius, parameter
s length of web (s )
w1
t thickness of face sheet
t nominal thickness of the internal facing
ni
t nominal thickness of the external facing
ne
t nominal thickness of the steel sheet
nom
t measured thickness
obs
t total thickness of the zinc layers (or similar protective coating)
zinc
t thinnest, tested face thickness
t thicker face thickness
v variance factor
w cover width
i
w bending deflection
B
w is the deflection caused by the elastic extension of the faces (without shear deformation)
b
w shear deflection
S
w is the deflection measured at time t
t
w ideal displacement at ultimate load based on the linear part of the deflection curve
u
w is the deflection caused by the elastic extension of the faces (without shear deformation)
x, y, z coordinates
x predicted value by the design expression
des
x 5 %-fractile value of population x
p
x test result
n
α coefficient of thermal expansion
α sound absorption
W
β design parameter
δ deviation
φ angle
φ creep coefficient
t
γ partial safety factor for variable actions
F
γ partial safety factor for the permanent action
G
γ material safety factor
M
γ partial safety factor for the variable action i
Q,i
λ thermal conductivity, λ (design value)
Design
λ declared thermal conductivity of the core material
c
λ declared thermal conductivity of the internal facing
fi
λ declared thermal conductivity of the external facing
fe
λ declared value of the thermal conductivity of the core material
Declared
λ design value of the thermal conductivity of the core material
Design
θ design parameter
σ stress, , standard deviation
σ compressive stress of the core at 10 % deformation
σ wrinkling stress
w
σ individual tested value for the wrinkling strength
w,obs,i
σ wrinkling stress of the thinnest face t
w,t1 1
σ wrinkling stress of a thicker face t
w,t2 2
σ wrinkling stress – apparent yield stress
yr
σ standard deviation of y
y
σ standard deviation of y
yn n
τ shear stress
Ψ combination coefficient
Ψ linear thermal transmittance of joints per metre length of panel (W/m·K) according to ISO 10211
j
ψ combination coefficient of a variable action i (see Table E.6)
ψ combination coefficient of a variable action i (i > 1) to be used in characteristic combinations
0i
ψ combination coefficient of the dominant action effect Q to be used in frequent combinations
11 k1
ψ combination coefficient of the other action effects Q (i > 1) to be used in frequent combinations
1i ki
ρ coefficient, density
ρ density of used glue in kilograms per cubic metre, i.e. density of uncured glue mixture, (kg/m )
glue
4.2 Abbreviated terms
EPS expanded polystyrene
EN European Norm
FPC factory production control
ISO International Standardisation Organisation
TT type test
MW mineral wool
NPD no performance determined
PCS gross calorific potential
PUR rigid polyurethane foam (the abbreviation PUR includes polyisocyanurate foam (PIR))
PF phenolic foam
XPS extruded polystyrene foam
5 Requirements, properties and test methods
5.1 Requirements for component materials
5.1.1 General
The product shall be manufactured with materials and components conforming to 5.1.2 to 5.1.4.
5.1.2 Metal facings
5.1.2.1 Steel
5.1.2.1.1 Steel faces
Steel faces (other than stainless steel) shall have minimum yield strength of 205 N/mm and shall conform
to the requirements of the appropriate standard given in Table 1.
For steels according to Table 1, the steel grade, nominal thickness and tolerance system of each face shall be
declared. Tolerances on thickness shall be according to the ―special or ―normal tolerances as described in
EN 10143:2006, Clause 6.
Table 1 — Standards for steel with metallic coating
Metallic coating Standard
Zinc, Zinc-Magnesium, 5 % Al-Zn, 55 % Al-Zn and Alumin-
EN 10346
ium-silicon
Differential zinc coating shall be permitted for the external face of a panel exposed to the climate for all core materials.
Organic protective coatings shall be selected according to their durability in the application environment.
Organic coated steel sheets shall conform to the requirements of EN 10169. Multi-layer coatings shall
conform to EN 508-1.
The panel manufacturer shall state the metal grade, thickness and tolerance system of each face. Tolerances
on thickness shall be according to “special” or “normal”. The thickness of steel facing sheets shall be
determined in accordance with ISO 16163.
NOTE Not all steels in Table 1 are suitable for sandwich panels in all the intended end uses.
5.1.2.1.2 Back face coating
If the metal face is bonded over its whole area to a rigid foam core with a closed cell structure, the reverse
side metallic coating mass shall be a minimum of 50 g/m .
When relevant to intended end use application, resistance of metallic protective coatings and organic back
face coat (duplex coating) against corrosion shall be ensured by laboratory tests. Minimum resistance of
backing coat shall be CPI2 according to EN 10169. Additionally, to the requirements in EN 10169 only slight
colour change (DE ≤ 2,0) shall be acceptable in the condensation-water test (in accordance with ISO 6270-1)
over 1 000 h.
The requirements in 5.1.2.1.2 are only applicable to back face coatings.
Measurement methods for metallic coating mass shall be followed according to the applicable standards in
the country of production.
5.1.2.2 Stainless steel faces
Stainless steel facings shall have a minimum yield strength of 205 N/mm . The chemical composition of
stainless steel faces and their physical properties shall conform to EN 10088-1.
The panel manufacturer shall state the metal grade, thickness and tolerance system of each face. Tolerances
on thickness shall be according to “special” or “normal” tolerances as described in ISO 9445-2:2009, Table 1.
The thickness of stainless steel facing sheets shall be determined in accordance with ISO 9445-2.
NOTE Not all stainless steels in EN 10088–1 are suitable for sandwich panels in all the intended end uses.
Reference can be made to EN 508–3, grades suitable for roofing.
5.1.2.3 Aluminium faces
The yield strength (0,2 %-strain limit) of the aluminium faces shall have a minimum value of 140 MPa. The
chemical composition, temper and mechanical properties of aluminium shall conform to ISO 6361-2.
Organic coated aluminium sheets shall conform to the requirements of EN 1396.
The panel manufacturer shall state the metal grade, thickness and tolerance system of each face. Tolerances
on thickness shall be according to “special” or “normal” tolerances. The thickness of aluminium facing sheets
shall be determined in accordance with ISO 6361-3.
NOTE Not all aluminium alloys covered by EN 485–2 or EN 1396 are suitable for sandwich panels in all the
intended end uses. Reference can be made to EN 508–2.
5.1.2.4 Copper faces
Copper facings shall have a design value of the stress at the 0,2 %-strain limit β (for simplification called
0,2
“yield strength“) of 180 N/mm . The chemical composition, temper, mechanical properties and thickness
tolerances of copper faces shall conform to EN 1172.
NOTE Only R240 and R290 grades in EN 1172 satisfy the requirement of 180 N/mm .
The panel manufacturer shall state the metal grade, thickness and tolerance system of each face. Tolerances
on thickness shall be according to “special” or “normal” tolerances. The thickness of copper facing sheets
shall be determined in accordance with EN 1172.
5.1.3 Core materials
5.1.3.1 Thermal performance
The declared and design thermal conductivity of core materials shall be determined in accordance with
5.2.2.
5.1.3.2 Thermal stability of core materials
The thermal stability of the core materials in a sandwich panel shall be evaluated through the durability
testing in accordance with 5.2.3
5.1.3.3 Density of core material
The density of core material indicates the mass of core material per unit of volume. When assessed in
accordance with the method A.8, the performance is expressed with a single value in kg/m together with
the tolerance in kg/m .
5.1.4 Adhesives and bonding
Adhesives and bonding shall conform to 5.2.1.6 and 5.2.3.1.

The adhesion between the core and the faces of the sandwich panel has a fundamental role in the satisfactory
performance of the sandwich panel. The surface preparation of the facing material shall be appropriate for
the adhesive or the method of adhesion.
5.2 Properties of sandwich panels
5.2.1 Mechanical resistance of the sandwich panel
5.2.1.1 General
For mechanical properties, unless stated otherwise, the mean value and the characteristic value (5 %
fractile value assuming a confidence level of 75 % for each population of test results) shall be determined in
accordance with ISO 12491.
Declared values shall be given to either two or three significant figures.
5.2.1.2 Shear strength (f ) and shear modulus (G )
Cv c
The declared values of the shear strength and shear modulus of the core shall be determined using the
appropriate test procedures from A.3 or A.4 in Annex A, in accordance with Table 2. The same test procedure
shall be used to determine both the shear strength and shear modulus of a panel. In principle, each test
method is suitable for panels with flat, lightly profiled or profiled facings.
The declared value of the shear strength shall be less than or equal to the characteristic value and shall be
declared by the manufacturer in megapascals (MPa).
Only the mean value of the shear modulus obtained from the available test results shall be declared. The
5 %-fractile value shall be recorded for FPC purposes in accordance with A.3 or A.4.
Table 2 — Alternative shear test methods
Test procedure Core and face mate- Formula for evaluation Comments
rials
Shear strength Shear modulus
A.3 – 2 load points All core and face ma- A.5 A.7 Basic procedure. May
terials be used in all situa-
(on small sample)
tions unless practical
requirements dictate
otherwise.
A.4 – 2 load points All core materials. A.10 A.7 Alternative to A.3.
(on full panel) Flat or lightly profiled For panels with one
faces or two profiled faces
wrinkling of the faces
One or both faces A.12 A.11
can occur
profiled
A.4 – Vacuum cham- All core materials. A.10 A.13 Alternative to the use
ber or air bag loading of 2 load points.
Flat or lightly
profiled faces
One or both faces A.15 A.14
profiled
5.2.1.3 Creep coefficient (φ )
t
The creep coefficients shall be determined according to A.6 and expressed as a number.
The creep coefficients shall be determined for all sandwich panels used as a roof designed to carry long
term or permanent loads, e.g. snow and self-weight.

5.2.1.4 Compressive strength (f ) or compressive stress (σ )
Cc 10
The compressive strength of the core f or its compressive stress at 10 % deformation σ (whichever is
Cc 10
reached first) shall be determined in accordance with the method given in A.2 and shall be declared by the
manufacturer in megapascals (MPa).
5.2.1.5 Shear strength after long-term loading (f long-term)
Cv
The shear strength after long term loading shall be determined in accordance with A.3.6. This value shall be
determined for all sandwich panels used as a roof designed to carry long term or permanent loads, e.g. snow
and self-weight. The declared value shall be less than or equal to the characteristic value ( f ) and shall be
Cv
declared by the manufacturer in megapascals (MPa).
NOTE The reduction obtained from the small-scale long-term test can be applied to panels where the shear
strength has been determined on the basis of large-scale tests to A.4 or calculated on the basis of A.3.5.3.
5.2.1.6 Cross panel tensile strength (f )
Ct
The characteristic value for cross panel tensile strength (tensile strength of the panel in the thickness
direction) shall be greater than 0,018 MPa when tested in accordance with A.1 and shall be declared by the
manufacturer in megapascals (MPa).
The declared values shall be less than or equal to the characteristic value.
NOTE Low tensile strength can reduce the wrinkling strength and increase its variability. Account is taken of this
in A.5.5.5 (k factor).
5.2.1.7 Bending moment capacity (M) and wrinkling stress (σ )
u w
The bending moment capacity shall be obtained by testing in accordance with A.5.
For panels with flat, lightly profiled or profiled faces, the wrinkling stress shall be calculated in accordance
with A.5.5 and the wrinkling strength shall be declared by the manufacturer in megapascals (MPa).
The declared wrinkling stress should generally be determined on the basis of the results of bending tests.
However, A.5.5.3 also allows a conservative value of the wrinkling stress to be calculated according to
Formula (A.34) and declared.
Wrinkling stress is related to bending moment by a simple mathematical relationship so that it is not
...

Date: 2025-02-25
ISO/DIS FDIS 17880:2025(en)
ISO/TC 61/SC 10/WG 10
Secretariat: 2SCC SCC
Date: 2026-04-27
Cellular plastics — Self-supporting metal faced sandwich panels
Plastiques alvéolaires — Panneaux sandwich à parements métalliques autoportants
FDIS stage
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication
may be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying,
or posting on the internet or an intranet, without prior written permission. Permission can be requested from either ISO
at the address below or ISO'sISO’s member body in the country of the requester.
ISO Copyright Office copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: + 41 22 749 01 11
Email: E-mail: [e-mail]
Website: www.iso.org
Published in Switzerland.
ii
ISO/DIS FDIS 17880:20252026(en)
Contents Page
Foreword . iv
Introduction . v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 4
4 Symbols and abbreviated terms . 6
4.1 Symbols . 6
4.2 Abbreviated terms . 11
5 Requirements, properties and test methods . 11
5.1 Requirements for component materials . 11
5.2 Properties of sandwich panels . 13
5.3 Actions and safety level requirements . 19
6 Testing, assessment and sampling methods . 20
6.1 General . 20
6.2 Type testing – TT . 20
6.3 Factory production control (FPC) . 25
6.4 Characteristic values from families of tests . 32
7 Classification and designation . 33
8 Marking, labelling and packaging . 34
8.1 Marking and labelling . 34
8.2 Packaging, transport, storage and handling . 34
Annex A (normative) Testing procedures for material properties . 35
Annex B (normative) Durability testing method for sandwich panels . 92
Annex C (informative) Fire tests . 107
Annex D (normative) Dimensional tolerances . 124
Annex E (informative) Design procedures . 140
Bibliography . 166

iii
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out through
ISO technical committees. Each member body interested in a subject for which a technical committee has been
established has the right to be represented on that committee. International organizations, governmental and
non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the
International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are described
in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the different types of
ISO document should be noted. This document was drafted in accordance with the editorial rules of the
ISO/IEC Directives, Part 2 (see www.iso.org/directives).
ISO draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). ISO takes no position concerning the evidence, validity or applicability of any claimed patent rights
in respect thereof. As of the date of publication of this document, ISO had not received notice of (a) patent(s)
which may be required to implement this document. However, implementers are cautioned that this may not
represent the latest information, which may be obtained from the patent database available at
www.iso.org/patents. ISO shall not be held responsible for identifying any or all such patent rights.
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and expressions
related to conformity assessment, as well as information about ISO's adherence to the World Trade
Organization (WTO) principles in the Technical Barriers to Trade (TBT), see www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 61, Plastics, Subcommittee SC 10, Cellular
plastics.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.
iv
ISO/DIS FDIS 17880:20252026(en)
Introduction
This document has been developed with cellular plastics as the core. It has been eventually modified to include
other materials, such as mineral wool.
v
ISO/DIS 17880:2024(en)
DRAFT International Standard
Cellular plastics — Self-supporting metal faced sandwich panels for
exterior use
1 Scope
This document specifies requirements for factory made, self-supporting, double skin metal-‑faced insulating
sandwich panels where the insulating core materials are intended to be but not limited to cellular plastics and
mineral wool as defined below.
The sandwich panels are intended for discontinuous laying in the following applications:
a) a) roofs and roof cladding;
b) b) external walls and wall cladding.
The insulating core materials covered by this document are rigid polyurethane foam (PUR), polyisocyanurate
foam (PIR), expanded polystyrene foam (EPS), extruded polystyrene foam (XPS), phenolic foam (PF) and
mineral wool. Sandwich panels with edge details that utilize different materials from the main insulating core
are included in this document. Sandwich panels used in outdoor cold storage applications are included in this
document.
This document does not cover the following:
— sandwich panels with a declared thermal conductivity for the insulating core material greater than
0,06 W/mK at 10 °C, or greater than 0,06 W/mK at 23℃; °C;
— sandwich panels consisting of two or more clearly defined layers of different insulating core materials
(multi-layered);
— sandwich panels consisting of more than one metal sheet per face;
— sandwich panels with perforated facing(s);
— curved sandwich panels;
— indoor cold storage applications.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content constitutes
requirements of this document. For dated references, only the edition cited applies. For undated references,
the latest edition of the referenced document (including any amendments) applies.
ISO 354:2003, Acoustics — Measurement of sound absorption in a reverberation room
ISO 717--1, Acoustics — Rating of sound insulation in buildings and of building elements — Part 1: Airborne
sound insulation
ISO 834--1, Fire-resistance tests — Elements of building construction — Part 1: General requirements
ISO/TR 834-3, Fire-resistance tests — Elements of building construction — Part 3: Commentary on test method
and guide to the application of the outputs from the fire-resistance test
ISO 834-ISO 834-4, Fire-resistance tests — Elements of building construction — Part 4: Specific requirements
for loadbearing vertical separating elements
ISO 834--5, Fire-resistance tests — Elements of building construction — Part 5: Specific requirements for
loadbearing horizontal separating elements
ISO 834--8, Fire-resistance tests — Elements of building construction — Part 8: Specific requirements for non-
loadbearing vertical separating elements
ISO 834--9, Fire-resistance tests — Elements of building construction — Part 9: Specific requirements for non-
loadbearing ceiling elements
ISO 845, Cellular plastics and rubbers –— Determination of apparent density
ISO 1182, Reaction to fire tests for products — Non-combustibility test
ISO 4354, Wind actions on structures
ISO 4355, Bases for design of structures — Determination of snow loads on roofs
ISO 4898, Rigid cellular plastics — Thermal insulation products for buildings — Specifications
ISO 6270--1, Paints and varnishes — Determination of resistance to humidity — Part 1: Condensation (single-
sided exposure)
ISO 6361--2, Wrought aluminium and aluminium alloys — Sheets, strips and plates — Part 2: Mechanical
properties
ISO 6361--3, Wrought aluminium and aluminium alloys — Sheets, strips and plates — Part 3: Strips: Tolerances
on shape and dimensions
ISO 6892--1, Metallic materials — Tensile testing — Part 1: Method of test at room temperature
ISO 6946, Building components and building elements — Thermal resistance and thermal transmittance —
Calculation methods
ISO 8145, Thermal insulation; mineral wool board for overdeck insulation of roofs — Specification
ISO 8301, Thermal insulation — Determination of steady-state thermal resistance and related properties — Heat
flow meter apparatus
ISO 8302, Thermal insulation — Determination of steady-state thermal resistance and related properties —
Guarded hot plate apparatus
ISO 9194, Bases for design of structures — Actions due to the self-weight of structures, non-structural elements
and stored materials — Density
ISO 9229, Thermal insulation — Vocabulary
ISO 9445--2:2009, Continuously cold-rolled stainless steel — Tolerances on dimensions and form — Part 2: Wide
strip and plate/sheet
ISO/DIS FDIS 17880:20242026(en)
ISO 10140-1:2021, Acoustics - — Laboratory measurement of sound insulation of building elements - — Part 1:
Application rules for specific products
ISO 10140-2:2021, Acoustics - — Laboratory measurement of sound insulation of building elements - — Part 2:
Measurement of airborne sound insulation
ISO 10211, Thermal bridges in building construction — Heat flows and surface temperatures — Detailed
calculations
ISO 10456, Building materials and products — Hygrothermal properties — Tabulated design values and
procedures for determining declared and design thermal values
ISO 11654, Acoustics — Sound absorbers for use in buildings — Rating of sound absorption
ISO 11925--2, Reaction to fire tests — Ignitability of products subjected to direct impingement of flame — Part
2: Single-flame source test
ISO 12468--1, External exposure of roofs to fire — Part 1: Test method
ISO/TR 12468--3, External exposure of roofs to fire — Part 2: Classification of roofs3: Commentary
ISO 12491, Statistical methods for quality control of building materials and components
ISO 12576-1, Thermal insulation — Insulating materials and products for buildings — Conformity control
systems”
ISO 13784--1:2014, Reaction to fire test for sandwich panel building systems — Part 1: Small room test
ISO 13784--2:2020, Reaction-to-fire tests for sandwich panel building systems — Part 2: Test method for large
rooms
ISO 13785--1, Reaction-to-fire tests for façades — Part 1: Intermediate-scale test
ISO 13785--2, Reaction-to-fire tests for façades — Part 2: Large-scale test
ISO 13943, Fire safety — Vocabulary
ISO 16163, Continuously hot-dipped coated steel sheet products — Dimensional and shape tolerances
ISO 22111, Bases for design of structures — General requirements
ISO 29465, Thermal insulating products for building applications — Determination of length and width
ISO 29466, Thermal insulating products for building applications — Determination of thickness
ISO 29469, Thermal insulating products for building applications — Determination of compression behaviour
ISO 29470, Thermal insulating products for building applications — Determination of the apparent density
ISO 29765, Thermal insulating products for building applications — Determination of tensile strength
perpendicular to faces
EN 508--1, Roofing products from metal sheet — Specification for self-supporting products of steel, aluminium
or stainless steel sheet — Part 1: Steel
EN 1172, Copper and copper alloys — Sheet and strip for building purposes
EN 1396, Aluminium and aluminium alloys — Coil coated sheet and strip for general applications —
Specifications
EN 1990:2002 + A1:2005 + A1:2005/AC:2010, Eurocode - Basis of structural design
EN 10088--1, Stainless steels — Part 1: List of stainless steels
EN 10143:2006, Continuously hot-dip metal coated steel sheet and strip — Tolerances on dimensions and shape
EN 10169, Continuously organic coated (coil coated) steel flat products — Technical delivery conditions
EN 10204, Metallic products - Types of inspection documents
EN 12865, Hygrothermal performance of building components and building elements — Determination of the
resistance of external wall systems to driving rain under pulsating air pressure
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 9229, ISO 13943 and the following
apply.
ISO and IEC maintain terminologicalterminology databases for use in standardization at the following
addresses:
— — IEC Electropedia: available at
— — ISO Online browsing platform: available at https://www.iso.org/obp
— 3.1IEC Electropedia: available at https://www.electropedia.org/
3.1
auto-adhesive bond
self-adhesion of the core to the face(s) occurring automatically without the use of an adhesive
Note 1 to entry: This technique is used for producing sandwich panels by foaming.
3.2 3.2
bending moment capacity
maximum bending moment recorded during a test on an individual panel
3.3 3.3
bending resistance
characteristic value of bending moment capacity determined on the basis of a test series
3.4 3.4
bond,
bonding
adhesion between the face(s) and the core normally provided by an approved adhesive
3.5 3.5
core
layer of material, having thermal insulating properties, which is bonded between two metal faces, creating a
sandwich panel
ISO/DIS FDIS 17880:20242026(en)
3.6 3.6
durability
ability of the panel to withstand the environmental effects and accommodate the consequent decrease in
mechanical strength with time caused by factors such as temperature, humidity, freeze-thaw cycles and their
various combinations
3.7 3.7
edge
longitudinal edge
side of the panel where adjacent panels join together in the same plane
3.8 3.8
face
facing
flat, lightly profiled or profiled thin metal sheet firmly bonded to the core
3.9 3.9
flat face
face without any rolled or pressed profile or raised strengthening rib
3.10 3.10
lightly profiled face
face with a rolled or pressed profile not exceeding 5 mm in depth
3.11 3.11
profiled face
face with a rolled or pressed profile exceeding 5 mm in depth
3.12 3.12
incompletely bonded panel
panel in which one or both faces is incompletely bonded
3.13 3.13
joint
interface between two panels where the meeting edges have been designed to allow the panels to join together
in the same plane
Note 1 to entry: The joint can incorporate interlocking parts that enhance the mechanical properties of the system as well
as improving the thermal, acoustic and fire performance and restricting air movement.
Note 2 to entry: The term 'joint' does not refer to a junction between cut panels or a junction where the panels are not
installed in the same plane.
3.14 3.14
lamella
core material consisting of mineral wool that has been cut and orientated with the fibres perpendicular to the
facings prior to bonding
3.15 3.15
lightly profiled facing
facing with a rolled or pressed profile not exceeding 5 mm in depth
3.16 3.16
pre-manufactured
pre-formed
component or material that is supplied to the manufacturer ready for direct incorporation into the sandwich
panel as a core
3.17 3.17
sandwich panel
building product consisting of two metal faces positioned on either side of a core that is a thermally insulating
material, which is firmly bonded to both faces so that the three components act compositely when under load
3.18 3.18
self-supporting sandwich panel
panel capable of supporting, by virtue of its materials and shape, its self-weight and in the case of panels fixed
to spaced structural supports all applied loadings (e.g. snow, wind, internal air pressure), and transmitting
these loadings to the supports
3.19 3.19
shift
period of production during a working day, normally 6 h to 8 h but can be less
3.20 3.20
side lap
folded area of one or both facing materials along the longitudinal edge of the panel which engages with the
adjacent panel to form an interlocking or overlapping joint
3.21 3.21
wrinkling strength
characteristic value of wrinkling stress (3.21(3.21))
3.22 3.22
wrinkling stress
stress in the compressed face of a panel undergoing failure in bending, where the failure mode takes the form
of a "wrinkle" extending over the full width of the panel near the section of maximum bending moment
4 Symbols and abbreviated terms
4.1 Symbols
For the purposes of this document, the following symbols and abbreviated terms apply.
A cross-sectional area of the specimen determined from the measured dimensions
A cross sectional area of the core based on measured depth d
C c
A area of the carrier
c
A measured area of cross-section of the top face based on measured metal thickness;
F1
AF2 measured area of cross-section of the bottom face based on measured metal thickness;
A area of facing sheet in square metres (m2)
glue
B bending stiffness, overall width of the panel/specimen
B minimum width of uncut core material across a line of cut ends
min
Bobs bending stiffness with tobs and eobs
ISO/DIS FDIS 17880:20242026(en)
B flexural rigidity
S
C ratio, design value of a serviceability criterion
C limiting design value of the relevant serviceability criterion expressed as the maximum
d
serviceability limit state design stress or limit on deflection taking into account the material
partial factor for serviceability limit state design γ
M
Ctr spectrum adaptation term calculated with A-weighted urban traffic noise
D overall depth of the panel
E modulus of elasticity, design value of the effect of an action
E mean of the characteristic values of the tensile and compressive moduli of the core material
C
ECc compressive E-modulus of the core
E tensile E-modulus of the core
Ct
E E-modulus of the top face
F1
E E-modulus of the bottom face
F2
F force, load, support reaction
F self-weight of the panel
G
F load at the end of the linear part of the load-deflection curve
lin
F test value of reaction capacity
Ri
F ultimate load
u
G shear modulus, permanent action
G shear modulus of the core
C
GC, red reduced shear modulus of the core
G characteristic value of the permanent action
k
I moment of inertia
I moment of inertia of the profiled face(s) (sum if both faces are profiled)
F
IS moment of inertia of the sandwich part (see Annex EAnnex E))
L span, distance,
L width of support plate
s
M bending moment
MDu Bending moments at ultimate limit state to determine σ yrσyr
M M M
Su Du Su
Mu bending moment capacity
N axial compressive force
Q variable action
Q characteristic value of the dominant variable action
k1
Qki characteristic value of the non-dominant variable action i (I > 1)
R resistance
R test result modified to correspond to the design values of metal thickness
adj,i
RDUR, R24 tensile strength
R degree of reflection relative to magnesium oxide = 100 %
G
R characteristic resistance
k
R result of test number I
obs,i
R external surface resistance (m K/W)
se
Rsi internal surface resistance (m K/W)
R sound reduction index
w
S shear rigidity, value of a load effect, characteristic value of an action
S characteristic value of an action
ki
T temperature
U thermal transmittance value of the panel,
U thermal transmittance value of the panel including the influence of the panel joints
d,s
V shear force
a distance apart of clips
b width of test specimen, width of plate, width of ribs/valleys, bowing
b width of the clips
c
d depth of face profile or stiffeners,
d nominal thickness of the core (ignoring the thickness of the facings) and the geometry of the
C
main profiles), see Figure A.18Figure A.18 and Figure A.19Figure A.19
dd design thickness of the panel
d depth of stiffeners
S
e distance between centroids of faces, base of natural logarithms (e = 2,718 282)
e additional thickness of the external face
e
e additional thickness of the internal face
i
e distance between the faces on basis of measured geometry
obs
f strength, yield stress , reduction factor
fC mean compressive strength of the core
f compressive strength of the core
Cc
f cross panel tensile strength after time t
Ct
f shear strength of the core
Cv
fCv, red reduced shear strength of the core
f thermal transmittance contribution factor
joint
f thermal transmittance contribution factor with clip
joint, c
f thermal transmittance contribution factor without (no) clip
joint, nc
fy design yield stress
f measured yield stress
y,obs
h height of profile
h thickness of adhesive in millimetres (mm)
glue
ISO/DIS FDIS 17880:20242026(en)
k correction factor, distribution parameter
k reduction factor for cut ends in pre-formed cores
v
l length, deviation
m mass
madhesive amount of adhesive in grams per square metre (g/m ) from measurements during production
m mass of the carrier
c
m mass of the carrier and adhesive
a+c
m amount of adhesive in grams per square metre (g/m ) from measurements on a manufactured
glue
panel
m mass of facing + glue in grams (g)
m2 mass of facing in grams (g)
n number of tests, number of screws, number of webs
p pitch of profile
q live load
r radius, parameter
s length of web (s )
w1
t thickness of face sheet
t nominal thickness of the internal facing
ni
tne nominal thickness of the external facing
t nominal thickness of the steel sheet
nom
t measured thickness
obs
t total thickness of the zinc layers (or similar protective coating)
zinc
t thinnest, tested face thickness
t thicker face thickness
v variance factor
wi cover width
w bending deflection
B
w is the deflection caused by the elastic extension of the faces (without shear deformation)
b
w shear deflection
S
wt is the deflection measured at time t
w ideal displacement at ultimate load based on the linear part of the deflection curve
u
w is the deflection caused by the elastic extension of the faces (without shear deformation)
x, y, z coordinates
xdes predicted value by the design expression
x 5 %-fractile value of population x
p
x test result
n
α coefficient of thermal expansion
α sound absorption
W
β design parameter
δ deviation
φ angle
φt creep coefficient
γ partial safety factor for variable actions
F
γ partial safety factor for the permanent action
G
γ material safety factor
M
γQ,i partial safety factor for the variable action i
λ thermal conductivity, λ (design value)
Design
λ declared thermal conductivity of the core material
c
λ declared thermal conductivity of the internal facing
fi
λfe declared thermal conductivity of the external facing
λ declared value of the thermal conductivity of the core material
Declared
λ design value of the thermal conductivity of the core material
Design
θ design parameter
σ stress, , standard deviation
σ compressive stress of the core at 10 % deformation
σ σ wrinkling stress
w w
σ wσw,obs,i individual tested value for the wrinkling strength
σ σ wrinkling stress of the thinnest face t
w w,t1 1
σ σ wrinkling stress of a thicker face t
w w,t2 2
σ σ wrinkling stress – apparent yield stress
yr yr
σ yσy standard deviation of y
σ σ standard deviation of y
yn yn n
τ shear stress
Ψ combination coefficient
Ψj linear thermal transmittance of joints per metre length of panel (W/m·K) according to ISO
ψ0 combination coefficient of a variable action i (see Table E.6Table E.6))
ψ combination coefficient of a variable action i (i > 1) to be used in characteristic combinations
0i
ψ ψ combination coefficient of the dominant action effect Q to be used in frequent combinations
11 11 k1
ψ combination coefficient of the other action effects Q (i > 1) to be used in frequent combinations
1i ki
ρ coefficient, density
ρ density of used glue in kilograms per cubic metre, i.e. density of uncured glue mixture, (kg/m )
glue
ISO/DIS FDIS 17880:20242026(en)
4.14.2 Abbreviated terms
EPS expanded polystyrene
EN European Norm
FPC factory production control
ISO International Standardisation Organisation
TT type test
MW mineral wool
NPD no performance determined
PCS gross calorific potential
PUR rigid polyurethane foam (the abbreviation PUR includes polyisocyanurate foam (PIR))
PF phenolic foam
XPS extruded polystyrene foam
5 Requirements, properties and test methods
5.1 Requirements for component materials
5.1.1 General
The product shall be manufactured with materials and components conforming to 5.1.25.1.2 to 5.1.45.1.4.
5.1.2 Metal facings
5.1.2.1 Steel
5.1.2.1.1 Steel faces
Steel faces (other than stainless steel) shall have minimum yield strength of 205 N/mm and shall conform to
the requirements of the appropriate standard given in Table 1Table 1.
For steels according to Table 1Table 1,, the steel grade, nominal thickness and tolerance system of each face
shall be declared. Tolerances on thickness shall be according to the ―special or ―normal tolerances as
described in EN 10143:2006, Clause 6.
Table 1— Standards for steel with metallic coating
Metallic coating Standard
Zinc, Zinc-Magnesium, 5 % Al-Zn, 55 % Al-Zn and
EN 10346
Aluminium-silicon
Differential zinc coating shall be permitted for the external face of a panel exposed to the climate for all core
materials.
Organic protective coatings shall be selected according to their durability in the application environment.
Organic coated steel sheets shall conform to the requirements of EN 10169. Multi-layer coatings shall conform
to EN 508-1.
The panel manufacturer shall state the metal grade, thickness and tolerance system of each face. Tolerances
on thickness shall be according to “special” or “normal”. The thickness of steel facing sheets shall be
determined in accordance with ISO 16163.
NOTE Not all steels in Table 1Table 1 are suitable for sandwich panels in all the intended end uses.
5.1.2.1.2 Back face coating
If the metal face is bonded over its whole area to a rigid foam core with a closed cell structure, the reverse side
metallic coating mass shall be a minimum of 50 g/m .
When relevant to intended end use application, resistance of metallic protective coatings and organic back
face coat (duplex coating) against corrosion shall be ensured by laboratory tests. Minimum resistance of
backing coat shall be CPI2 according to EN 10169. Additionally, to the requirements in EN 10169 only slight
colour change (DE ≤ 2,0) shall be acceptable in the condensation-water test (in accordance with ISO 6270--1)
over 1 000 h.
The requirements in 5.1.2.1.25.1.2.1.2 are only applicable to back face coatings.
Measurement methods for metallic coating mass shall be followed according to the applicable standards in
the country of production.
5.1.2.2 Stainless steel faces
Stainless steel facings shall have a minimum yield strength of 205 N/mm . The chemical composition of
stainless steel faces and their physical properties shall conform to EN 10088-1.
The panel manufacturer shall state the metal grade, thickness and tolerance system of each face. Tolerances
on thickness shall be according to “special” or “normal” tolerances as described in ISO 9445-2:2009, Table 1.
The thickness of stainless steel facing sheets shall be determined in accordance with ISO 9445--2.
NOTE Not all stainless steels in EN 10088–1 are suitable for sandwich panels in all the intended end uses. Reference
can be made to EN 508–3, grades suitable for roofing.
5.1.2.3 Aluminium faces
The yield strength (0,2 %-strain limit) of the aluminium faces shall have a minimum value of 140 MPa. The
chemical composition, temper and mechanical properties of aluminium shall conform to ISO 6361-2.
Organic coated aluminium sheets shall conform to the requirements of EN 1396.
The panel manufacturer shall state the metal grade, thickness and tolerance system of each face. Tolerances
on thickness shall be according to “special” or “normal” tolerances. The thickness of aluminium facing sheets
shall be determined in accordance with ISO 6361-3.
NOTE Not all aluminium alloys covered by EN 485–2 or EN 1396 are suitable for sandwich panels in all the intended
end uses. Reference can be made to EN 508–2.
5.1.2.4 Copper faces
Copper facings shall have a design value of the stress at the 0,2 %-strain limit β (for simplification called
0,2
“yield strength“) of 180 N/mm . The chemical composition, temper, mechanical properties and thickness
tolerances of copper faces shall conform to EN 1172.
NOTE Only R240 and R290 grades in EN 1172 satisfy the requirement of 180 N/mm .
ISO/DIS FDIS 17880:20242026(en)
The panel manufacturer shall state the metal grade, thickness and tolerance system of each face. Tolerances
on thickness shall be according to “special” or “normal” tolerances. The thickness of copper facing sheets shall
be determined in accordance with EN 1172.
5.1.3 Core materials
5.1.3.1 Thermal performance
The declared and design thermal conductivity of core materials shall be determined in accordance with
5.2.25.2.2.
5.1.3.2 Thermal stability of core materials
The thermal stability of the core materials in a sandwich panel shall be evaluated through the durability testing
in accordance with 5.2.35.2.3
5.1.3.3 Density of core material
The density of core material indicates the mass of core material per unit of volume. When assessed in
accordance with the method A.8A.8,, the performance is expressed with a single value in kg/m together with
the tolerance in kg/m .
5.1.4 Adhesives and bonding
Adhesives and bonding shall conform to 5.2.1.65.2.1.6 and 5.2.3.15.2.3.1.
The adhesion between the core and the faces of the sandwich panel has a fundamental role in the satisfactory
performance of the sandwich panel. The surface preparation of the facing material shall be appropriate for the
adhesive or the method of adhesion.
5.2 Properties of sandwich panels
5.2.1 Mechanical resistance of the sandwich panel
5.2.1.1 General
For mechanical properties, unless stated otherwise, the mean value and the characteristic value (5 % fractile
value assuming a confidence level of 75 % for each population of test results) shall be determined in
accordance with ISO 12491.
Declared values shall be given to either two or three significant figures.
5.2.1.2 Shear strength (fCv) and shear modulus (Gc)
The declared values of the shear strength and shear modulus of the core shall be determined using the
appropriate test procedures from A.3A.3 or A.4A.4 in Annex AAnnex A,, in accordance with Table 2Table 2.
The same test procedure shall be used to determine both the shear strength and shear modulus of a panel. In
principle, each test method is suitable for panels with flat, lightly profiled or profiled facings.
The declared value of the shear strength shall be less than or equal to the characteristic value and shall be
declared by the manufacturer in megapascals (MPa).
Only the mean value of the shear modulus obtained from the available test results shall be declared. The 5 %-
fractile value shall be recorded for FPC purposes in accordance with A.3A.3 or A.4A.4.
Table 2— Alternative shear test methods
Test procedure Core and face Formula for evaluation Comments
materials
Shear strength Shear modulus
A.3A.3 – 2 load All core and face A.5A.5 A.7A.7 Basic procedure.
points materials May be used in all
situations unless
(on small sample)
practical
requirements dictate
otherwise.
A.4A.4 – 2 load All core materials. A.10A.10 A.7A.7 Alternative to
points A.3A.3.
Flat or lightly
(on full panel) profiled faces For panels with one
or two profiled faces
One or both faces A.12A.12 A.11A.11
wrinkling of the
profiled
faces can occur
A.4A.4 – Vacuum All core materials. A.10A.10 A.13A.13 Alternative to the
chamber or air bag use of 2 load points.
Flat or lightly
loading
profiled faces
One or both faces A.15A.15 A.14A.14
profiled
5.2.1.3 Creep coefficient (φ )
t
The creep coefficients shall be determined according to A.6A.6 and expressed as a number.
The creep coefficients shall be determined for all sandwich panels used as a roof designed to carry long term
or permanent loads, e.g. snow and self-weight.
5.2.1.4 Compressive strength (fCc) or compressive stress (σ10)
The compressive strength of the core fCc or its compressive stress at 10 % deformation σ10 (whichever is
reached first) shall be determined in accordance with the method given in A.2A.2 and shall be declared by the
manufacturer in megapascals (MPa).
5.2.1.5 Shear strength after long-term loading (fCv long-term)
The shear strength after long term loading shall be determined in accordance with A.3.6A.3.6. This value shall
be determined for all sandwich panels used as a roof designed to carry long term or permanent loads, e.g.
snow and self-weight. The declared value shall be less than or equal to the characteristic value (f ) and shall
Cv
be declared by the manufacturer in megapascals (MPa).
NOTE The reduction obtained from the small-scale long-term test can be applied to panels where the shear strength
has been determined on the basis of large-scale tests to A.4A.4 or calculated on the basis of A.3.5.3A.3.5.3.
5.2.1.6 Cross panel tensile strength (fCt)
The characteristic value for cross panel tensile strength (tensile strength of the panel in the thickness
direction) shall be greater than 0,018 MPa when tested in accordance with A.1A.1 and shall be declared by the
manufacturer in megapascals (MPa).
The declared values shall be less than or equal to the characteristic value.
ISO/DIS FDIS 17880:20242026(en)
NOTE Low tensile strength can reduce the wrinkling strength and increase its variability. Account is taken of this in
A.5.5.5A.5.5.5 (k factor).
5.2.1.7 Bending moment capacity (M ) and wrinkling stress (σ )
u w
The bending moment capacity shall be obtained by testing in accordance with A.5A.5.
For panels with flat, lightly profiled or profiled faces, the wrinkling stress shall be calculated in accordance
with A.5.5A.5.5 and the wrinkling strength shall be declared by the manufacturer in megapascals (MPa).
The declared wrinkling stress should generally be determined on the basis of the results of bending tests.
However, A.5.5.3A.5.5.3 also allows a conservative value of the wrinkling stress to be calculated according to
(A.34)Formula (A.34) and declared.
Wrinkling stress is related to bending moment by a simple mathematical relationship so that it is not
necessary to declare both the bending resistance and the wrinkling strength.
For a panel with a profiled face in compression, the bending resistance shall be declared together with the
span of the test specimen. Optionally, the wrinkling stress can be declared.
If it is intended that design shall be carried out on the basis of calculations in accordance with
Annex EAnnex E,, it is preferable to declare the wrinkling strength wherever possible.
NOTE Declaration of the wrinkling stresses are essential for design on the basis of testing.
5.2.1.8 Bending moment capacity and wrinkling stress over a central support
The bending moment capacity over a central support shall be determined in accordance with A.7A.7. For
sandwich panels with flat or lightly profiled faces, the wrinkling stress shall then be calculated in accordance
with A.5.5A.5.5.
The bending moment capacity over a central support is required when sandwich panels which are continuous
over two or more spans are to be designed by calculation in accordance with Annex EAnnex E. In such cases,
the comparison of the design values of resistance according to E.2E.2 is usually carried out in terms of stresses.
If the sandwich panel has one or more profiled faces, the determination of the ultimate compressive
(wrinkling) stress from the bending moment capacity requires calculation in accordance with E.8.5E.7.5. It is
recommended that this calculation is carried out at the time of testing.
5.2.2 Thermal transmittance
The thermal transmittance value for the panel (U), incorporating the manufacturer’s declared thermal
conductivity for the core material (λ ) and the joints and any profiled facings, shall be determined in
Declared
accordance with A.11A.11.
Both λ , together with the test temperature (at 10 °C or 23 °C) and the U -value shall be declared.
Declared d,s
5.2.3 Durability and other long-term effects
5.2.3.1 Reduction of tensile strength with time as a consequence of ageing (durability)
Sandwich panels shall satisfy the criteria for reduction in tensile strength in accordance with the relevant test
method DUR1 and DUR2 (see Table 3Table 3)) as described in Annex BAnnex B.
Durability tests shall be applied to sandwich panels designed for external applications. They are based on the
accelerated ageing effect of temperature or humidity, which from long-term experience are critical for each
core material.
The durability tests may be used to assess the performance of internal sandwich panels.
NOTE 1 These tests evaluate the reduction of tensile strength as a result of temperature or humidity on a pass/fail
basis.
NOTE 2 The durability requirement covers the performance of all essential structural components of the panel, for
example backface coatings, adhesion layers and core material.
PUR sandwich panels manufactured using the blowing agents covered within ISO 4898 and a combination of
these blowing agents, but excluding CO2 blown foams shall be considered to satisfy the durability
requirements without testing. PUR sandwich panels manufactured with other blowing agents shall be tested
according to test DUR1 and the colour reflectivity levels shall be declared (see B.2.5B.2.5).).
Table 3— Durability tests and deemed to satisfy criteria
Test method
Insulating core material Note
(Annex B(Annex B))
Polystyrene (EPS or XPS) DUR1 DUR1 including wedge test (B.5(B.5))
No test required for sandwich panels manufactured
Polyurethane (PUR), – using the blowing agents covered within ISO 4898,
DUR1
but excluding foams blown solely by CO
auto-adhesive bond
Other blowing agents shall be tested to DUR1
No test required for sandwich panels manufactured
using the blowing agents covered within ISO 4898,
but excluding CO blown foams.
Polyurethane (PUR), – 2
DUR1
Other blowing agents shall be tested to DUR1
adhesive bond
including the wedge test (B.4(B.4))
The wedge test (B.4(B.4)) shall be carried out
DUR1, thermal shock B.6B.6
PF sandwich panels with an adhesive bond shall be
Phenolic (PF) and repeated loading
tested to DUR1 including the wedge test (B.4(B.4))
B.5B.5
Mineral Woolwool (MW) DUR2 DUR2 including the wedge test (B.5(B.5))
5.2.3.2 Resistance to point loads and access loads – roof sandwich panels
The ability of a sandwich panel to resist point loads and access loads shall be determined in accordance with
A.10.1A.10.1. For applications where there will be more frequent access than occasional foot traffic (see
NOTE), the procedure described in A.10.2A.10.2 shall also be carried out.
NOTE Point loads are loads resulting from a single person walking on the panel, for occasional access both during
and after erection.
5.2.4 Fire characteristics
5.2.4.1 Reaction to fire
The reaction to fire of sandwich panels shall be determined according to ISO 13784-1 using the ignition source
specified in ISO 13784-1:2014, 8.1 with burner heat output programme specified in ISO 13784-1:2014, 10.2
and Figure 8 (i.e. 100 kW for 10 m
...